imlemented CameraSpotDetector

lib/screens/metering/components/camera_container/bloc_container_camera.dart

@@ -11,10 +11,8 @@ import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:lightmeter/interactors/metering_interactor.dart';
 import 'package:lightmeter/platform_config.dart';
 import 'package:lightmeter/screens/metering/communication/bloc_communication_metering.dart';
-import 'package:lightmeter/screens/metering/communication/event_communication_metering.dart'
+import 'package:lightmeter/screens/metering/communication/event_communication_metering.dart' as communication_event;
-    as communication_event;
+import 'package:lightmeter/screens/metering/communication/state_communication_metering.dart' as communication_states;
-import 'package:lightmeter/screens/metering/communication/state_communication_metering.dart'
-    as communication_states;
 import 'package:lightmeter/screens/metering/components/camera_container/event_container_camera.dart';
 import 'package:lightmeter/screens/metering/components/camera_container/models/camera_error_type.dart';
 import 'package:lightmeter/screens/metering/components/camera_container/state_container_camera.dart';
@@ -57,6 +55,7 @@ class CameraContainerBloc extends EvSourceBlocBase<CameraContainerEvent, CameraC
     on<ZoomChangedEvent>(_onZoomChanged);
     on<ExposureOffsetChangedEvent>(_onExposureOffsetChanged);
     on<ExposureOffsetResetEvent>(_onExposureOffsetResetEvent);
+    on<ExposureSpotChangedEvent>(_onExposureSpotChangedEvent);
   }
 
   @override
@@ -166,9 +165,7 @@ class CameraContainerBloc extends EvSourceBlocBase<CameraContainerEvent, CameraC
   }
 
   Future<void> _onZoomChanged(ZoomChangedEvent event, Emitter emit) async {
-    if (_cameraController != null &&
+    if (_cameraController != null && event.value >= _zoomRange!.start && event.value <= _zoomRange!.end) {
-        event.value >= _zoomRange!.start &&
-        event.value <= _zoomRange!.end) {
       _cameraController!.setZoomLevel(event.value);
       _currentZoom = event.value;
       _emitActiveState(emit);
@@ -188,6 +185,14 @@ class CameraContainerBloc extends EvSourceBlocBase<CameraContainerEvent, CameraC
     add(const ExposureOffsetChangedEvent(0));
   }
 
+  Future<void> _onExposureSpotChangedEvent(ExposureSpotChangedEvent event, Emitter emit) async {
+    if (_cameraController != null) {
+      _cameraController!.setExposurePoint(event.offset);
+      _cameraController!.setFocusPoint(event.offset);
+      _emitActiveState(emit);
+    }
+  }
+
   void _emitActiveState(Emitter emit) {
     emit(
       CameraActiveState(

lib/screens/metering/components/camera_container/components/camera_preview/components/camera_spot_detector/widget_camera_spot_detector.dart

@@ -0,0 +1,68 @@
+import 'package:flutter/material.dart';
+import 'package:lightmeter/res/dimens.dart';
+
+class CameraSpotDetector extends StatefulWidget {
+  final ValueChanged<Offset> onSpotTap;
+
+  const CameraSpotDetector({
+    required this.onSpotTap,
+    super.key,
+  });
+
+  @override
+  State<CameraSpotDetector> createState() => _CameraSpotDetectorState();
+}
+
+class _CameraSpotDetectorState extends State<CameraSpotDetector> {
+  Offset? spot;
+
+  @override
+  Widget build(BuildContext context) {
+    return LayoutBuilder(
+      builder: (_, constraints) => GestureDetector(
+        behavior: HitTestBehavior.opaque,
+        onTapDown: (TapDownDetails details) => onViewFinderTap(details, constraints),
+        child: Stack(
+          children: [
+            if (spot != null)
+              AnimatedPositioned(
+                duration: Dimens.durationS,
+                left: spot!.dx - Dimens.grid16 / 2,
+                top: spot!.dy - Dimens.grid16 / 2,
+                height: Dimens.grid16,
+                width: Dimens.grid16,
+                child: const _Spot(),
+              ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  void onViewFinderTap(TapDownDetails details, BoxConstraints constraints) {
+    setState(() {
+      spot = details.localPosition;
+    });
+
+    widget.onSpotTap(
+      Offset(
+        details.localPosition.dx / constraints.maxWidth,
+        details.localPosition.dy / constraints.maxHeight,
+      ),
+    );
+  }
+}
+
+class _Spot extends StatelessWidget {
+  const _Spot();
+
+  @override
+  Widget build(BuildContext context) {
+    return const DecoratedBox(
+      decoration: BoxDecoration(
+        color: Colors.white70,
+        shape: BoxShape.circle,
+      ),
+    );
+  }
+}

lib/screens/metering/components/camera_container/components/camera_preview/components/camera_view/widget_camera_view.dart

@@ -12,14 +12,17 @@ class CameraView extends StatelessWidget {
     final value = controller.value;
     return ValueListenableBuilder<CameraValue>(
       valueListenable: controller,
-      builder: (_, __, ___) => AspectRatio(
+      builder: (_, __, Widget? child) => AspectRatio(
         aspectRatio: _isLandscape(value) ? value.aspectRatio : (1 / value.aspectRatio),
-        child: value.isInitialized
+        child: Stack(
-            ? RotatedBox(
+          children: [
-                quarterTurns: _getQuarterTurns(value),
+            RotatedBox(
-                child: controller.buildPreview(),
+              quarterTurns: _getQuarterTurns(value),
-              )
+              child: controller.buildPreview(),
-            : const SizedBox.shrink(),
+            ),
+            child ?? const SizedBox(),
+          ],
+        ),
       ),
     );
   }
@@ -42,8 +45,6 @@ class CameraView extends StatelessWidget {
   DeviceOrientation _getApplicableOrientation(CameraValue value) {
     return value.isRecordingVideo
         ? value.recordingOrientation!
-        : (value.previewPauseOrientation ??
+        : (value.previewPauseOrientation ?? value.lockedCaptureOrientation ?? value.deviceOrientation);
-            value.lockedCaptureOrientation ??
-            value.deviceOrientation);
   }
 }

lib/screens/metering/components/camera_container/components/camera_preview/widget_camera_preview.dart

@@ -4,6 +4,7 @@ import 'package:lightmeter/data/models/metering_screen_layout_config.dart';
 import 'package:lightmeter/platform_config.dart';
 import 'package:lightmeter/providers/user_preferences_provider.dart';
 import 'package:lightmeter/res/dimens.dart';
+import 'package:lightmeter/screens/metering/components/camera_container/components/camera_preview/components/camera_spot_detector/widget_camera_spot_detector.dart';
 import 'package:lightmeter/screens/metering/components/camera_container/components/camera_preview/components/camera_view/widget_camera_view.dart';
 import 'package:lightmeter/screens/metering/components/camera_container/components/camera_preview/components/camera_view_placeholder/widget_placeholder_camera_view.dart';
 import 'package:lightmeter/screens/metering/components/camera_container/components/camera_preview/components/histogram/widget_histogram.dart';
@@ -12,8 +13,14 @@ import 'package:lightmeter/screens/metering/components/camera_container/models/c
 class CameraPreview extends StatefulWidget {
   final CameraController? controller;
   final CameraErrorType? error;
+  final ValueChanged<Offset> onSpotTap;
 
-  const CameraPreview({this.controller, this.error, super.key});
+  const CameraPreview({
+    this.controller,
+    this.error,
+    required this.onSpotTap,
+    super.key,
+  });
 
   @override
   State<CameraPreview> createState() => _CameraPreviewState();
@@ -31,7 +38,10 @@ class _CameraPreviewState extends State<CameraPreview> {
             AnimatedSwitcher(
               duration: Dimens.switchDuration,
               child: widget.controller != null
-                  ? _CameraPreviewBuilder(controller: widget.controller!)
+                  ? _CameraPreviewBuilder(
+                      controller: widget.controller!,
+                      onSpotTap: widget.onSpotTap,
+                    )
                   : CameraViewPlaceholder(error: widget.error),
             ),
           ],
@@ -43,16 +53,19 @@ class _CameraPreviewState extends State<CameraPreview> {
 
 class _CameraPreviewBuilder extends StatefulWidget {
   final CameraController controller;
+  final ValueChanged<Offset> onSpotTap;
 
-  const _CameraPreviewBuilder({required this.controller});
+  const _CameraPreviewBuilder({
+    required this.controller,
+    required this.onSpotTap,
+  });
 
   @override
   State<_CameraPreviewBuilder> createState() => _CameraPreviewBuilderState();
 }
 
 class _CameraPreviewBuilderState extends State<_CameraPreviewBuilder> {
-  late final ValueNotifier<bool> _initializedNotifier =
+  late final ValueNotifier<bool> _initializedNotifier = ValueNotifier<bool>(widget.controller.value.isInitialized);
-      ValueNotifier<bool>(widget.controller.value.isInitialized);
 
   @override
   void initState() {
@@ -89,6 +102,7 @@ class _CameraPreviewBuilderState extends State<_CameraPreviewBuilder> {
                     bottom: Dimens.grid16,
                     child: CameraHistogram(controller: widget.controller),
                   ),
+                CameraSpotDetector(onSpotTap: widget.onSpotTap)
               ],
             )
           : const SizedBox.shrink(),

lib/screens/metering/components/camera_container/event_container_camera.dart

@@ -1,3 +1,5 @@
+import 'package:flutter/gestures.dart';
+
 abstract class CameraContainerEvent {
   const CameraContainerEvent();
 }
@@ -53,3 +55,19 @@ class ExposureOffsetChangedEvent extends CameraContainerEvent {
 class ExposureOffsetResetEvent extends CameraContainerEvent {
   const ExposureOffsetResetEvent();
 }
+
+class ExposureSpotChangedEvent extends CameraContainerEvent {
+  final Offset offset;
+
+  const ExposureSpotChangedEvent(this.offset);
+
+  @override
+  bool operator ==(Object other) {
+    if (identical(this, other)) return true;
+    if (other.runtimeType != runtimeType) return false;
+    return other is ExposureSpotChangedEvent && other.offset == offset;
+  }
+
+  @override
+  int get hashCode => Object.hash(offset, runtimeType);
+}

lib/screens/metering/components/camera_container/widget_container_camera.dart

@@ -143,6 +143,9 @@ class _CameraViewBuilder extends StatelessWidget {
       builder: (context, state) => CameraPreview(
         controller: state is CameraInitializedState ? state.controller : null,
         error: state is CameraErrorState ? state.error : null,
+        onSpotTap: (value) {
+          context.read<CameraContainerBloc>().add(ExposureSpotChangedEvent(value));
+        },
       ),
     );
   }

test/screens/metering/components/camera/event_container_camera_test.dart

@@ -1,5 +1,7 @@
 // ignore_for_file: prefer_const_constructors
 
+import 'dart:ui';
+
 import 'package:lightmeter/screens/metering/components/camera_container/event_container_camera.dart';
 import 'package:test/test.dart';
 
@@ -41,4 +43,23 @@ void main() {
       });
     },
   );
+
+  group(
+    '`ExposureSpotChangedEvent`',
+    () {
+      final a = ExposureSpotChangedEvent(Offset(0.0, 0.0));
+      final b = ExposureSpotChangedEvent(Offset(0.0, 0.0));
+      final c = ExposureSpotChangedEvent(Offset(2.0, 2.0));
+      test('==', () {
+        expect(a == b && b == a, true);
+        expect(a != c && c != a, true);
+        expect(b != c && c != b, true);
+      });
+      test('hashCode', () {
+        expect(a.hashCode == b.hashCode, true);
+        expect(a.hashCode != c.hashCode, true);
+        expect(b.hashCode != c.hashCode, true);
+      });
+    },
+  );
 }